Spatio-temporal trends and climatology of atmospheric chlorinated hydrocarbons over Pakistan

Chlorinated hydrocarbons (CH) are emitted into the atmosphere by different anthropogenic activities and natural process, which could contribute to global warming and rapid melting of glaciers and cause serious health hazards. The objective of this research was to figure out the spatio-temporal distribution of CH concentration and the influence of climatic variables on CH concentration over Pakistan. Chlorinated hydrocarbons (CH) data was collected from the GEIA Database emissions dataset. The results indicated that CH were significantly distributed over Pakistan in different seasons. Highest concentration of CH was recorded in winter and autumn seasons as compared to the spring and summer seasons. The concentration of CH was maximum in winter season as compared to the other seasons. Spatial analysis indicated that CH concentration (1–1.2 kg/m 2 /s) was higher in the Punjab Province (Lahore, Rawalpindi, Gujrat, Sialkot, and Multan) as compared to the other Provinces, suggesting it could be due to high transport and industries in the region. Surface temperature and specific humidity showed significant positive correlation with CH across the Pakistan. Rainfall showed positive correlation with CH at the south part during spring and autumn seasons while on the north part of Pakistan during summer and winter seasons.The results suggest that CH could cause climate change through radiative forcing or climate forcing in Pakistan. Waste sector and solvent sector (30%) revealed higher level of CH during 2000. This study demonstrates the changing of climatic conditions in different seasons generate a special circumstance for accumulation and transportation of CH in Pakistan.